I like wipes (left/right/up/down/clock). This look nice. Pretty much anything that "fits" with what's going on (ie if you're going from a motion pic to another, try a shove).

Use Glow+keyframed levels to get an interesting look

I also like using page peel.
If you reduce the picture slightly in size using track motion, add some ready made corners, then it looks like a page in a photo album being turned over.

Fade to white / black always works well. So much depends on the music you're using.. upbeat tends to give you a bit more leeway while slower music calls for slower, more subtle transitions. "staying professional" is merely dependent on your audience. I've done montages in the past for corporate clients that reeked of Video Toaster transitions (actually done with a linear Toaster editor years ago) that were recieved with applause. Sometimes it's merely feeling out your audience too.

mike

What's cheesy for one is not for the other... and vice-versa.
I'd say: go with your feelings, skills and general knowledge of what have been done.

I have a word document of some ideas I have collected from the forums. Feel free to download it or email me ideas to add.

click the vegas link at the bottom

www.calderwood.org

cheroxy

My daughter and I did a project a year ago with a number of cheesey transitions (our fist attempt at editing)

To my surprise when played back to the high school students featured in the video and slide show they loved the transitions. Knowing the audience and testing with that audience is an important part of the process.